Oil burner



Feb. 169 @1943. F. RAVNSBECK OIL BURNER Filed May 3, 1941 Patented Feb. 16, 1943 oIL BURNER Fred Ravnsbeck, Chicago, Ill., assigner to Ace Engineering Co., Chicago, Ill., a. corporation of Illinois Application May 3, 1941, `Serial No. 391,629

4 Claims.

This invention relates to an oil burner of the type in which a rotary blower discharges air through a nozzle and the oil is discharged centrifugally into the air stream at the nozzle for atomization and admixture with the air.

One object of the invention is to provide an improved degree of atomization of the oil and a more thorough admixture thereof with the air than has been possible in previous structures.

Another object is to provide adjustable means controlling the discharge of oil and air for regulating the position and form of the combustion zone.

More specically, it is an object of the invention to provide in combination with a rotary blower having an air discharge nozzle, an axially located rotatable oil discharge member positioned to feed oil centrifugally across the air stream discharged by the blower and provided with an interposed tubular member also arranged to rotate, and forming an annular passage for the discharge of air in a generally axial direction so as to intercept the centrifugally discharged oil before it encounters the air stream from the nozzle of the blower.

Other objects and advantages will appear as the description proceeds.

In the drawing:

Figure l is a diametral sectional View of the blower of an oil burner, together with its air discharge nozzle and the oil delivery means with which this invention is concerned.

Figure 2 is an end elevation of a nozzle and associated parts, taken as indicated by the arrows at 2-2 on Figure l.

Figure 3 is a transaxial detail section taken as indicated at line 3-3 on Figure l.

The oil burner t which this invention is applied includes a housing l in which there is journaled a drive shaft 2 carrying the rotor 3 of a centrifugal air pump or blower having outwardly extending air passages 4. The air delivered from these passages in the outer portion of the casing l travels back toward the axis of the housing between vanes 5, and is discharged through a nozzle E which is located coaXially with the shaft 2. In Figure l the nozzle 6 is shown extending into a suitably formed opening 'l in a fixture 8 which may be understood as mounted on the front wall of the combustion chamber of a furnace or other heating plant with which the burner mechanism is associated.

The shaft 2 is made hollow so that its bore 2a may serve as an oil feed conduit to which it may be understood that the oil is supplied at a properly controlled rate by any suitable pump or other flow-inducing means, not shown. The outer end of the shaft supports a tubular terminal 9 whose inner diameter increases slightly toward its outer end, so that the oil delivered to this inner surface is carried by centrifugal force toward the outer end of the terminal 9 and is then discharged by centrifugal force therefrom. Preferably, the extreme end portion of the terminal 9 is formed as a flaring flange lil, as shown in Figure l.

The nozzle 6 is shown with an inwardly directed ange or lip l l at its outer end past which air discharged from the blower flows outwardly toward the combustion zone for admixture with the oil discharged from the tubular terminal 9. ln previous structures in which the mixing device consisted only of a nozzle, such as the part 1, and an oil discharging member, such as the part Q, there was a tendency for some of the oil to strike the lip of the nozzle and condense thereon, forming a deposit which interfered with subsequent action of the burner, and which, of course, denoted imperfect or improper mixing of the air and oil.

The operation of the device has been greatly improved, however, by the provisio-n of an interposed tubular member IZ extending within the nozzle but dimensioned to leave an annular passage I3 for the ow of air through the nozzle. The member l2 is also spaced from the tubular terminal 9, being supported coaxially thereon by means of a hub portion I4 fitted tightly onto the cylindrical surface of the hub l5 of the member S. As shown in Figure l, the hub l5 is screwed onto the end of the shaft 2 for rotation therewith, and the member l2, being thus secured to the hub l5, is also rotatable with thev shaft 2. The hub lll is provided with a pluralityof ports i6 through which a portion of the airY discharged by the blower will flow into the annular space Il formed between the part l2 and the tubular terminal This air will thus beprojected past the flaring flange il! of the part 9 so as to intercept the oil which is discharged centrifugally from the flange, itl, and the Velocity of the air stream issuing from the space ll will serve to break up the oil and deflect it forwardly so as to positively prevent any deposit of oil on the lip or fla-nge Il of the fixed nozzle B. If any oil discharged from the flange IQ of the tubular terminal 9 should lodge temporarily on the annular rim of the member I2, it will be thrown off by centrifugal force, since this member is rotating with the shaft 2, and to insure such release of any oil particles lodging on this rim, the inner surface of the rim is slightly flared, as seen at I2a.

The rotation of the ports I and of the parts 9 and I2 between which a portion of the air travels forward to the outlet will tend to produce some rotary motion of this annular column of air issuing at |23, whereas the air discharged through the space I3 in the outer nozzle 6 will be traveling forward' without any considerable rotary component. Hence, the oil discharged centrifugally from the rotating terminal 9 is first attacked and deflected by the whirling inner column of air issuing from the passage I2, and its direction is then further altered by encounter with the outer stream of air from the nozzle 6, with the result that the oil particles will be quite thoroughly atomized and intermingled with the air, with no opportunity to lodge and accumulate on any part of the mixing device itself.

The tubular member I2, although fitted tightly onto the cylindrical hub I5, may be adjusted thereon in axial direction to vary the position of its terminal lip I2a with relation to the flared lip I of the tube 9. And, as shown, the nozzle 6 is also adjustable in axial direction, being carried by threaded engagement with a supporting ange I8 at the air outlet of the housing l, so that it may be screwed inwardly or outwardly in axial direction. Preferably, the outer end of the tubular member I2 is externally reduced to form an outwardly facing shoulder I2b, and the lip or ange Il of the nozzle 6 is positioned outwardly of this shoulder so that axial adjustment of the nozzle operates to vary the space between the shoulder I2b and the lip II, and thus serves to regulate the flow of air through the nozzle. A set screw I9 is provided for securing the nozzle 6 at adjusted position. With these adjustments the mixing device may be adapted to various specific conditions, so that the resulting flame propagation may be best suited to the particular form of the furnace or combustion chamber with which the oil burner is employed.

While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and re-arrangements of the parts may be made without departing from the spirit and scope of the invention, and that the same is not limited to the particular form herein shown and described, except in so far as indicated by the appended claims.

I claim as my invention:

l. In an oil burner in combination a rotary blower having an axially disposed air outlet nozzle and a hollow drive shaft providing an oil feed passage, a terminal cup xed to the outer end of said shaft as a continuation of the oil feed passage thereof, the rotation of said shaft and cup serving to discharge oil centrifugally adjacent the air outlet nozzle, and a tubular member disposed in the space between the outer surface of said terminal cup and the inner surface of the blower nozzle, forming an annular passage around said cup communicating with the interior of the blower through which passage a portion of the air discharged by the blower ows, and means connecting said tubular member to the shaft for rotation therewith, said tubular member having an external, transaxial shoulder adjacent its outer end and the nozzle having an inwardly extending, annular flange, said tubular member and said nozzle being relatively adjustable in axial direction to vary the space between said shoulder and said flange for regulating the flow of air through the nozzle.

2. In an oil burner in combination, a rotary blower having an axially disposed air outlet nozzle and a hollow drive shaft providing an oil feed passage, a terminal cup fixed to the outer end of said shaft as a continuation of the oil feed passage thereof, the rotation of said shaft and cup serving to discharge oil centrifugally adjacent the air outlet nozzle, and a tubular member disposed in the space between the outer surface of said terminal cup and the inner surface of the blower nozzle, forming an annular passage around said cup communicating with the interior of the blower through which passage a portion of the air discharged by the blower flows, and means connecting said tubular member to the shaft for rotation therewith, the outer end of the tubular member being reduced to form an outwardly facing, transaxial shoulder and the outer end of the nozzle having an inwardly projecting lip facing said shoulder, said nozzle being axially adjustable to vary the space between said shoulder and said lip.

3. In an oil burner in combination, a rotary blower having an axially disposed air outlet nozzle and a hollow drive shaft providing an oil feed passage, a terminal cup xed to the outer end of said shaft as a continuation of the oil feed passage thereof, the rotation of said shaft and cup serving to discharge oil centrifugally adjacent the air outlet nozzle, and a tubular member disposed in the space between the outer surface of said terminal cup and the inner surface of the blower nozzle, forming an annular passage around said cup communicating with the interior of the blower through which passage a portion of the air discharged by the blower flows, and means connecting' said tubular member to the shaft for rotation therewith, said tubular member being axially adjustable for shifting its outlet end relatively to the terminal cup, and the outlet nozzle of the blower being mounted for adjustment axially for varying the position of its outlet end with respect to the outlet end of said tubular member.

4. In an oil burner in combination, a rotary blower having an axially disposed air outlet nozzle and a hollow drive shaft providing an oil feed passage, a terminal cup fixed to the outer end of said shaft as a continuation of the oil feed passage thereof, the rotation of said shaft and cup serving to discharge oil centrifugally adjacent the air outlet nozzle, and a tubular member disposed in the space between the outer surface of said terminal cup and the inner surface of the blower nozzle, forming an annular passage around said cup communicating with the interior of the blower through which passage a portion of the air discharged by the blower flows, and means connecting said tubular member to the shaft for rotation therewith, said tubular member being axially adjustable for shifting its outlet end relatively to the end of the terminal cup, the air outlet nozzle and said tubular member having spaced, transaxial shoulders which denne a portion of the air outlet passage through the nozzle, and said nozzle being mounted for adjustment axially with respect to the tubular member for varying the capacity of said passage between said transaxial shoulders.

FRED RAVNSBECK. 

